Metal tubing coated with multiple layers of polymeric materials

摘要

A coated metal tubing arrangement comprises a metal tube. An inner layer of a first polymeric material is bonded to the tube to provide corrosion protection. The first polymeric material has a high crystallinity, a dampening factor of less than 0.05, and a flexural modulus of at least 100 MPa. An outer layer of a second polymeric material is extruded around the inner layer to absorb impact energies and to eliminate mechanical vibrations and acoustic noises. The second polymeric material has a dampening factor of at least 0.05 and a flexural modulus of less than 50 Mpa. The second polymeric material is a multi-phase polymer having at least one polymer component with a glass-transition temperature below room temperature.